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Identifying template watermarks under severe geometric distortions is a significant scientific problem in the current watermarking research for remote sensing images. We propose a novel watermarking algorithm that integrates the ring-shaped template watermark with the multiscale local contrast measure (LCM) method. In the embedding stage, the ring-shaped template watermark is embedded into the discrete Fourier transform (DFT) magnitude coefficients, converting the watermark into small targets in the DFT domain. During the detection stage, the multiscale LCM, a classic infrared small target detection method, enhances these small targets and generates a contrast map. Peak detection is then performed on the contrast map to determine the radius of the template watermark. Finally, circular edge local binarization is applied to extract the watermark information. The proposed method enables synchronization recovery of watermarks under blind conditions. The experimental results demonstrate that the method possesses strong robustness against various geometric attacks such as rotation, scaling, translation, and cropping. It outperforms comparative algorithms in terms of robustness and also exhibits good imperceptibility. [ABSTRACT FROM AUTHOR]

The surrounding rock of coal mining face often contains numerous micro-cracks, and these microcracks greatly restrict the mechanical strength of the rock. Mechanical properties of rock degraded by joints and fissures in rock,, taking the Mesozoic three-stream pluton granite in Dandong City, Liaodong uplift area as an example,, establish a particle flow model and use the "trial and error method" to repeatedly calibrate the microscopic parameters until they are consistent with the actual situation,, uniaxial compression tests were performed on rock masses with different fissures, and 16 orthogonal discrete element numerical simulation experiments with 4 factors and 4 levels were carried out. Based on multiple linear regression analysis, the influence of four factors on the mechanical properties of granite was analysed, and the influence of single factor on the macro-mechanical properties of granite was studied through numerical experiments. The results show that the effect of the crack geometry on the peak strength of granite is greater than the effect on the elastic modulus of granite; The order of the influence degree of the crack geometric characteristic parameters on the peak strength is the crack Y-axis position component > the crack X-axis position component > the crack length > the crack inclination angle; The order of the influence degree of the crack geometric characteristic parameters on the elastic modulus is the crack X-axis position component > the crack Y-axis position component > the crack length > the crack inclination angle; The crack initiation position gradually moves to both ends of the crack as the angle increases. The specimen is mainly dominated by tension cracks, and the crack tip is accompanied by local shear failure; The longer the crack length, the lower the peak strength of the granite, and the worse the stability; The positional change of primary microcracks in granite mainly changes the peak strength and post-peak stress-strain state of the rock sample, but has no significant effect on the elastic modulus. The research results have certain reference value for predicting the mechanical properties of fractured granite.

Purpose: No data exist on perioperative strategies for enhancing recovery after posterior retroperitoneoscopic adrenalectomy (PRA). Our objective was to determine whether a multimodality adrenal fast-track and enhanced recovery (AFTER) protocol for PRA can reduce recovery time, improve patient satisfaction and maintain safety. Methods: Thirty primary aldosteronism patients were included. Fifteen patients were treated with ‘standard-of-care’ PRA and compared with 15 in the AFTER protocol. The AFTER protocol contains: a preoperative information video, postoperative oral analgesics, early postoperative mobilisation and enteral feeding, and blood pressure monitoring at home. The primary outcome was recovery time. Secondary outcomes were length of hospital stay, postoperative pain and analgesics requirements, patient satisfaction, perioperative complications and quality of life (QoL). Results: Recovery time was much shorter in both groups than anticipated and was not significantly different (median 28 days). Postoperative length of hospital stay was significantly reduced in AFTER patients (mean 32 vs 42 h, CI 95%, p = 0.004). No significant differences were seen in pain, but less analgesics were used in the AFTER group. Satisfaction improved amongst AFTER patients for time of admission and postoperative visit to the outpatient clinic. There were no significant differences in complication rates or QoL. Conclusion: Despite no difference in recovery time between the two groups, probably due to small sample size, the AFTER protocol led to shorter hospital stays and less analgesic use after surgery, whilst maintaining and even enhancing patient satisfaction for several aspects of perioperative care. Complication rates and QoL are comparable to standard-of-care. [ABSTRACT FROM AUTHOR]

Textural morphology is an important factor influencing dry friction, and few studies have been conducted regarding the effects of single- and multi-shape textures on dry tribological properties. In this work, six types of textures including single- and multi-shape textures were produced on 40Cr steel samples by using a nanosecond laser. Reciprocating sliding tests under dry friction were conducted using a pin-on-disc friction tester. The influences of textured surfaces with different textures on tribological properties were investigated. Results showed that tribological properties were affected by different textural morphologies. The dimple-textured surface had the highest friction coefficient, followed by the groove-textured surface. The sinusoidal-textured surface had the lowest friction coefficient. The friction coefficients of multi-shape textured surfaces were lower than those of non-textured surfaces but higher than those of sinusoidal-textured surfaces. The wear properties of the tested surfaces were consistent with the friction-coefficient results. The sinusoidal- and sinusoidal–groove-textured surfaces can be considered as the optimum choices for dry reciprocating friction. [ABSTRACT FROM AUTHOR]